class email.headerregistry.ContentTransferEncoding Handles the Content-Transfer-Encoding header. cte Valid values are 7bit, 8bit, base64, and quoted-printable. See RFC 2045 for more information.

bytearray.rsplit(sep=None, maxsplit=-1) Split the binary sequence into subsequences of the same type, using sep as the delimiter string. If maxsplit is given, at most maxsplit splits are done, the rightmost ones. If sep is not specified or None, any subsequence consisting solely of ASCII whitespace is a separator. Except for splitting from the right, rsplit() behaves like split() which is described in detail below.

functools.cmp_to_key(func) Transform an old-style comparison function to a key function. Used with tools that accept key functions (such as sorted(), min(), max(), heapq.nlargest(), heapq.nsmallest(), itertools.groupby()). This function is primarily used as a transition tool for programs being converted from Python 2 which supported the use of comparison functions. A comparison function is any callable that accept two arguments, compares them, and returns a negative number for less-than, zer

kevent.filter Name of the kernel filter. Constant Meaning KQ_FILTER_READ Takes a descriptor and returns whenever there is data available to read KQ_FILTER_WRITE Takes a descriptor and returns whenever there is data available to write KQ_FILTER_AIO AIO requests KQ_FILTER_VNODE Returns when one or more of the requested events watched in fflag occurs KQ_FILTER_PROC Watch for events on a process id KQ_FILTER_NETDEV Watch for events on a network device [not available on Mac OS X] KQ_FILTER_SIGNAL

HMAC.digest() Return the digest of the bytes passed to the update() method so far. This bytes object will be the same length as the digest_size of the digest given to the constructor. It may contain non-ASCII bytes, including NUL bytes. Warning When comparing the output of digest() to an externally-supplied digest during a verification routine, it is recommended to use the compare_digest() function instead of the == operator to reduce the vulnerability to timing attacks.

apply_defaults() Set default values for missing arguments. For variable-positional arguments (*args) the default is an empty tuple. For variable-keyword arguments (**kwargs) the default is an empty dict. >>> def foo(a, b='ham', *args): pass >>> ba = inspect.signature(foo).bind('spam') >>> ba.apply_defaults() >>> ba.arguments OrderedDict([('a', 'spam'), ('b', 'ham'), ('args', ())]) New in version 3.5.

class codecs.StreamReader(stream, errors='strict') Constructor for a StreamReader instance. All stream readers must provide this constructor interface. They are free to add additional keyword arguments, but only the ones defined here are used by the Python codec registry. The stream argument must be a file-like object open for reading text or binary data, as appropriate for the specific codec. The StreamReader may implement different error handling schemes by providing the errors keyword arg

audioop.bias(fragment, width, bias) Return a fragment that is the original fragment with a bias added to each sample. Samples wrap around in case of overflow.

ipaddress.ip_network(address, strict=True) Return an IPv4Network or IPv6Network object depending on the IP address passed as argument. address is a string or integer representing the IP network. Either IPv4 or IPv6 networks may be supplied; integers less than 2**32 will be considered to be IPv4 by default. strict is passed to IPv4Network or IPv6Network constructor. A ValueError is raised if address does not represent a valid IPv4 or IPv6 address, or if the network has host bits set. >>

POP3.noop() Do nothing. Might be used as a keep-alive.